Drilling apparatus



Feb. 26, 1952 J. c. STATON DRILLING APPARATUS Fi led May 8, 194'? 2SI-IEETS-SHEET 1 gwuwwbom Feb. 26, 1952 J. c. STAT ON DRILLING APPARATUS2 SHEETS-SHEET 2 Filed May 8, 1947 im AI l James. C. Stator? PatentedFeb. 26 1952 2,586,878 panama APPARATUS James C. Staton, Corpus Christi,Tex., assignmto Eastman Oil Well Survey Company, Denver, 0010., acorporation of Delaware Application May 8, 1947, Serial No. 746,712

Claims.

This invention relates to new and useful improvements in drillingapparatus.

One object of the invention is to provide an improved apparatus whereina whipstock is detachably connected to a drill pipe or stem so that itmay be lowered and raised within the well bore by means of said pipe;the apparatus including an improved drilling assembly having means fordrilling a full-gauge, oflfset bore when drilling oil of the whipstockface occurs, whereby subsequent reaming or hole-enlarging operations arenot necessary to complete said offset bore. An important object of theinvention is to provide an apparatus which combines a removable-typewhipstock with an improved drilling assembly, with said assembly havingnormally retracted reaming means which is automatically expanded intoreaming or cutting position after the offset drilling operation isbegun, whereby reaming or enlargement of the well bore is accomplishedat the same time that the offset bore is drilled.

Another object of the invention is to provide an improved drillingapparatus or assembly having a drill bit at its lower end and havingexpansible reaming means spaced above said bit, with said reaming meansbeing resiliently maintained in a retracted position and being movableoutwardly into cutting position by the imposition of a predeterminedweight upon the assembly, whereby expansion of the reaming means iseffected when desired and after the drilling operation is begun; saidreaming means being constructed so as to immediately and automaticallyreturn to its retracted position as soon as the predetermined weight onthe apparatus or assembly is released.

A further object of the invention is to provide an improved drillingapparatus, of the character described, wherein reamer cutting blades arepivotally mounted on the body of the apparatus and wherein an expandingelement which is arranged to co-act with said blades is telescopicallymounted with relation to the blades, whereby when said element is movedwith respect to the blades, the latter are expanded into cuttingposition; said expanding element being moved when the weight of thedrill pipe or stem is imposed upon the apparatus during the drillingoperation to automatically expand the blades when the drilling operationis begun.

Still another object of the invention is to provide a combined whipstockand drilling apparatus wherein said apparatus is connected to whip- 2stock by means of a left-hand thread connection, whereby detachment ofthe apparatus from the whipstock may be effected by rotating theapparatus in a direction opposite to the direction of rotation which isrequired for normal drilling.

The construction designed to carry out the invention will be hereinafterdescribed together with other features of the invention.

The invention will be more readily understood from a reading of thefollowing speciflcationand by reference to the accompanying drawing,wherein an example of the invention is shown, and wherein:

Figure 1, is a view partly in section and partly in elevation of theimproved drilling apparatus, constructed in accordance with theinvention and combined with a removable-type whipstock,

Figure 2 is a similar view showing the drilling apparatus detached fromthe whipstock and also showing the position of said apparatus after ithas drilled off of the whipstock face,

Figure 3 is an enlarged, transverse, vertical, sectional view of thedrilling apparatus with the reaming cutters in a normally retractedposition,

Figure 4 is a similar view showing the reaming cutters moved to anexpanded or cutting position,

Figure 5 is an enlarged, horizontal; cross-sectional view taken on theline 5-'-5 of Figure 3, and

Figure 6 is an enlarged, horizontal, cross-sectional view taken on theline 66 of Figure 4.

In the drawings, the numeral l0 designates a Whipstock or deflectingtool which is constructed of a wedge-shaped body portion H having aninclined guide surface l2. The upper end of the body II has an integralsection [3 and the upper end of the section has a recovery collar I4integral therewith. The section I3 is substantially a straight wallsection and as will be explained, the drilling apparatus A is disposedopposite this section when said apparatus is connected to the whipstock.It is noted that the whip-stock is of the removable type, that is, it isarranged to be lowered and raised within the well bore B by means of thedrill pipe I5 which has connection with the drilling apparatus orassembly A. This type of whipstock is illustrated in the prior patent toMcVicar No. 1,970,761.

The drilling apparatus A which is combined with the whipstock 10comprises a main housing or cylinder 16 which has itslower end connected19 which forms a cylinder and an internal annular shoulder orenlargement 26 is formed within the housing at the lower end of thiscylinder. Below the internal shoulder 20, the housing is provided withdiametrically opposed, radially extending slots 2| within which reamerblades 22 are movable. As illustrated in Figures and 6.

tain the reamer blades in a retracted or inwardv position with respectto the housing, a coil spring 24 has its ends secured to the lowerportions of the blades, said spring functioning to hold said lower endsinwardly of the casing. It will be apparent that when the blades moveoutwardly through the slots 2| to the position shown in Figure 4, saidblades assume a cutting position and upon rotation of the housing willeffect a reaming operation of the bore which has been drilled by thedrill bit 18.

For moving the reamer blades 22 to an outward or expanded position, alongitudinally movable expanding element is movable between thediametrically opposed blades. lustrated in Figures 3 and 4, the element25 is in the form of a tubular shank which has its upper end preferablymade integral with a piston member 26, the latter being movable withinthe cylinder l9. The lower end of the expanding member is flaredoutwardly as indicated at 21 and.

longitudinal grooves 28 which are adapted to receive the rear edgesofthe reamer blades, are formed in the side wall of said element.Because of these grooves the blades and the main housing IE will berotated with the drill stem. When the piston 26 and its expandingelement 25 are in the position shown in Figure 3, said expanding elementis in a raised position with respect to the reamer blades 22 and in suchposition, the coil spring 24 holds said blades in a retracted or innerposition. When the piston 26 is moved downwardly within its cylinder,the expanding element moves downwardly with respect to the reamer blades22, whereby the flared lower end 21 of the expanding element co-actswith the rear edges of the blades which swing said blades outwardly intoan expanding or cutting position. Of course, this outward swingingmovement of the blades is against the tension of the coil spring 24which connects the blades. So long as the expanding element is in thelowered position (Figure 6), the blades 22 are extended outwardly and arotation of the apparatus will result in carrying out the reamingoperation.

In order to retract the blades 22, it is only necessary that the piston26 and its expanding element 25 be moved upwardly with respect to saidblades and as said element returns to the position shown in Figure 3,the connecting coil spring 24 will immediately retract the blades. Whenin a retracted position, the outer longitudinal cutting edges of theblades are substantially within the confines of the outer diameter ofthe housing l6 so that said blades will not hang up as the assembly islowered or raised within the well bore.

For controlling the movement of the piston 26 and its associatedexpanding element 25, said piston is formed with an upwardly projectingAs is clearly il- 3' tubular extension 29 which is made integraltherewith. The extension 29 projects through an opening 30 in the upperend of the housing 16 and has its upper portion enlarged at 3l,- wherebyan external annular shoulder 32 is provided on the exterior thereof. Theextreme upper end of the extension 29 is coupled, to the drill pipe l5,whereby th'en'tire assembly is suspended from said pipe. The extension29 is formed with an axial bore 33 and a reduced bore 34 which extendsentirely through said extension, piston 26 and expanding elements 25 sothat circulation downwardly through the device to the reamer blades 22and drill bit 18 may be accomplished.

In order to maintain the piston 26 in its raised position so that aninclined beveled shoulder 35 on said piston may engage an internalbeveled seat 36 within the housing, a spring 31 surrounds the reducedlower portion of the extension and is confined between the upper end ofthe housing I6 and the external shoulder 32 on said extension. Thisspring is relatively strong and is of a predetermined tension andobviously exerts its pressure to urge the extension upwardly withrespect to the housing; thus, the piston 26 is normally maintained in araised position within its cylinder with the shoulder 35 at its upperend engaging the seat 36 within said housing. It is obvious that inorder to move the piston 26 downwardly, a weight suflicient to collapsethe spring 31 must be imposed on the extension 29. Collapse of thespring is accomplished by imposing the weight of the drill pipe or steml5 upon the member, after the drill bit l8 has engaged the formation andis holding the housing l6 stationary.

For connecting the drill apparatus or assembly A to the whipstock I0,the enlarged upper portion 3| of the extension 29 is formed with aseries of coarse left-hand threads 38 which are disposed externallythereof. Co-acting coarse internal threads 39 are provided within therecovery collar M of the whipstock l0 and make it possible to detachablyconnected the extension 29 of the drilling apparatus or assembly A tosaid collar.

- The connected position of the parts is illustrated in Figure 1 and insuch position, the drilling apparatus or assembly A is disposed oppositethe straight wall section l3 of the whipstock; at this t me the reamerblades 22 are in a retracted position.

In order to make it possible to orient the whipstock so that its guideface I2 is disposed in a proper azimuthal position or direction, thetubular extension is provided with a magnet 40 which is mounted in itswall. When the threads 38 and 39 are coupled together to connect thedrilling apparatus or assembly A to the whipstock I0, the magnet 40 isdisposed in the vertical plane in which the whipstock guide face isdirected. Thus, by using any of the well known methods of determiningthe position of the magnet 40, it is possible to determine in whichdirection the whipstock face is pointing so that proper orientation ofthe whipstock may be carried out and subsequent drilling in a desireddirection accomplished. An example of the methods which may be employedfor locating the position of the magnet and, therefore, the azimuthalposition of the whipstock face [2 are illustrated in the patents to R.S. Hyer No. 2,120,670 and L. C. Miller No. 2,327,658.

In the operation, the drilling apparatus or as sembly A is coupled tothe recovery ring l4 of the whipstock M by connecting the coarseleft-hand threads 38 of the extension 29 to the internal aaaaare threads39 within the collar. In this position, the drilling apparatus abuts orextends contiguously to the straight wall section l3 of the whipstockIII, as shown in Figure 1 and at this time the relatively strong spring31 is maintaining the extension 29 raised with respect to the housingIt.

It is evident that the extension telescopes the housing and so long asthe spring 31 urges the extension upwardly with respect to the housing,the piston 26 is in its raised position within the cylinder I9 of saidhousing. At this time, the expanding element 25 connected to said pistonis raised with respect to the reamer blades 22 (Figure 3) and saidblades are held in their inneror retracted position by the coil spring24-.

Obviously since the drilling apparatus or assembly which is attached tothe drill pipe [5, is coupled to the whipstock, the drill pipe may beutilized to lower the complete assembly into position within the wellbore B. The whipstock is lowered until it strikes a cement plug Cprovided for the purpose or engages the formation at the lower end ofthe bore. Upon reaching the lower end of the bore, the position of thewhipstock face l2, that is the direction in which this surface isfacing, may be determined by lowering a magnetic instrument (not shown)through the drill pipe into a position opposite the magnet 40. By meansof a photographic record obtained by said instrument, the position ofthe magnet may be determined, whereby the azimuthal position of theguide face of the whipstock may be ascertained. After the azimuthalposition of the whipstock face is known it is obvious that a rotationmay be imparted thereto to dispose said face in a desired direction so,that subsequent drilling may be performed in a desired direction. Ofcourse, it may not be necessary or required that the direction orposition of the whipstock face be known, in which case the determinationof the position of the magnet 40 need not be accomplished. After settingof the whipstock, the drill pipe is rotated in a direction to uncouplethe left-hand threads 38 and 39. It is noted that the frictionalengagement of the whipstock with either the cement plug or the formationis sufficient to hold the recovery collar stationary so that a rotationof the drill pipe will accomplish uncoupling of the threads 38 and 39.

After the drilling apparatus or assembly A is uncoupled from thewhipstock, said apparatus is lowered downwardly and the drill bit I8 isguided by the inclined face l2 of said whipstock into engagement withthe formation. The operator will know the whipstock is uncoupled because the drill stem can move freely downwardly. When the drill bit l8engages the formation, the drill pipe is rotated and suflicient weightis imposed upon the drill bit to perform the drilling operation. Theoperator will know when sufficient weight is imposed because if too muchweight is imposed the stem will have a quick dropping movement due tocompression of spring 31. This weight issufiicient to force the bit 18into the formation but the spring 31 is strong enough to prevent anytelescoping movement of the extension 29 with respect to the reamerblade housing [6 so that at this time, the reamer blades remain in aretracted position. Drilling by the bit 18 continues in this manneruntil the pilot hole or til weight is sufficient to collapse the spring31 which normally prevents telescoping of the extension 29 with respectto the housing 15. Collapse of the spring 31 allows the extension tomove downwardly with respect to the housing, whereby the piston 26 andits expanding element 25 are moved downwardly with relation to thepivoted reamer blades 22. It will be obvious that as the expandingelement 25 moves between the blades 22, said blades are swung outwardlyto their expanded or reaming position, as illustrated in Figure 4. It isnoted that downward movement of the piston 26 and its expanding element25 are limited by the lower end of the piston 26 striking the internalshoulder 20 within the cylinder l9. So long as the weight suflicient tomaintain the spring 31 collapsed is imposed on the assembly, the reamerblades 22 remain in an expanded position and the continued rotation ofthe drill pipe results in the blades carrying out a reaming or holeenlarging operation as a follow up to the pilot bore D being drilled bythe bit l8.

The blades 22 are arranged to move outwardly a distance which will besufiicient to form a full gauge bore and, therefore, the deflected orangular bore which is drilled by the assembly will be of the same sizeas the original well bore B. Drilling of the deflected or angular boremay be continued until said deflected bore has suflicient depth tosubsequently guide an ordinary bit thereinto.

To remove the assembly, it is only necessary to lift the drill pipe andthe drilling apparatus upwardly until the threads 38 of the apparatusengage the internal threads 39 of the recovery collar, after which thesethreads may be recoupled. Subsequent upward lifting of the drill pipe toremove the apparatus A will simultaneously remove the whipstock l0therewith.

From the foregoing it will be seen that a relatively simple apparatuswhich permits the drilling of a deflected or angular bore to full gaugeis provided. The coupling arrangement through the use of the left-handcoarse threads eliminates the use of shear pins and this obviates thepossibility of unintentionally disconnecting the drilling apparatus fromthe whipstock. The reaming blades 22 are normally maintained in aretracted position and may be held in this position as long as desired.In other words, the expansion of the reamer blades is controlled solelyby the operator through the imposition of the weight on the drill pipe.There may be instances where it is not desirable to actuate the reamerblades and in such case, drilling of the deflected or angular bore willbe accomplished by the drill bit l8 and this may be done by imposingonly sufficient weight to cause digging by the bit l8 without collapsingthe spring 31.

The foregoing description of the invention is explanatory thereof andvarious changes in the size, shape and materials, as well as in thedetails of the illustrated construction may be made, within the scope ofthe appended claims, without departing from the spirit of the invention.

What I claim and desire to secure by Letters Patent is:

l. A rotary earth bore drilling apparatus including, a deflecting tool,a drilling assembly detachably connected to said deflecting tool, saidassembly comprising a rotatable drill pipe, an earth drill bit rotatablyconnected to the lower end of said pipe, an expansible reaming meansmounted in the drill pipe above the bit and normally in a retractedposition, the apparatus be- 7 ing lowered into a well bore as a unit tolocate the deflecting tool within the bore, means for disconnecting thedrilling assembly from the tool to permit a rotary earth drillingoperation to be carried out with the drill bit rotating relatively toand being guided in its direction by the deflecting tool, and meansactuated by relative longitudinal movement of the drill pipe withrespect to the reaming means for expanding thereaming means wherebyreaming of the bore drilled by the drill bit may be accomplished withoutremoving the apparatus from said bore.

2. A rotary earth bore drilling apparatus including, a deflecting tool,a drilling assembly detachably connected with the deflecting tooltracted position, means operable from the surface for disconnecting thedrilling assembly from the tool when the latter is properly locatedwithin the bore, whereby subsequent lowering and rotation of the drillpipe results in the drill bit performing a drilling operation with saidbit rotating relatively to and being guided by the deflecting tool, andmeans actuated by relative longitudinal movement of the drill pipe withrespect to the reaming means for expanding the reaming means, wherebymovement of the reaming means into and out of reaming position iscontrolled from the surface.

3. A drilling apparatus as set forth in claim 1, wherein the deflectingtool is a whipstock having a recovery collar at its upper end and alsowherein the detachable connection between the drilling assembly and thewhipstock comprises coarse left-hand threads on said assembly and withinthe collar of said whipstock.

4. A drilling apparatus as set forth in claim 2, wherein the deflectingtool is a whipstock having a recovery collar at its upper end and alsowherein the detachable connection between the drilling assembly and thewhipstock comprises coarse left-hand threads on said assembly and withinthe collar of said whipstock.

5. A drilling apparatus as set forth in claim 2, wherein the expansiblereaming means comprises pivoted cutting blades which are mounted toswing inwardly and outwardly in a radial direction with respect to thedrill pipe.

6. A rotary earth bore drilling apparatus including, a deflecting tool,a drilling assembly detachabiy connected with the deflecting toolwhereby said assembly and tool may be lowered into the bore as a unit toposition said tool at the desired depth in the bore, said drillingassembly comprising, a rotatable drill pipe, a reamer housing havingexpansible cutting blades which are normally in a retracted position,means for connecting the reamer housing to the drill pipe to permit saidpipe and housing to be moved axially with respect to each other, meansactuated by the movement of the pipe axially with respect to the housingfor expanding the cutter blades, a drill bit secured to the lower end ofthe drill pipe below the reamer housing, and means actuated from thesurface by manipulation of the drill pipe for detaching the drillingassembly from the deflecting tool, whereby a drilling operation may becarried out.

7. A rotary earth bore drilling apparatus including, a deflecting tool,a drilling assembly dev normally in a retracted position, means for con-4 necting the reamer housing to the drill pipe to permit said pipe andhousing to be moved axially with respect to each other, means actuatedby the movement of the pipe axially with respect to the housing forexpanding the cutter blades, a drill bit rotatably connected to thelowerend of the drill pipe below the reamer housing, and means actuatedfrom the surface by manipulation of the drill pipe for detaching thedrilling assembly from the deflecting tool, whereby a drilling operationmay be carried out, axial movement of the drill pipe with respect to thereamer housing being effected by theimposition of a predetermined weightupon said drilling assembly through the drill pipe, whereby expansionand retraction of the reamer blades may be controlled from the surface.

8. A rotary earth bore drilling apparatus including, a deflecting tool,a drilling assembly detachably connected with the deflecting toolwhereby said assembly and tool may be lowered into the bore as a unit toposition said tool at the desired depth in the bore, said drillingassembly comprising, a rotatable drill pipe, a reamer hous ing havingexpansible reaming cutters which are normally in a retracted position, atelescoping connection between the housing and the drill pipe wherebythese parts may move a limited distance with respect to each other,means actuated by the movement of the drill pipe with relation to thehousing for expanding the reaming cutters, resilient means associatedwith the telescoping connection for normally holding the pipe andhousing in a position with the reamer cutters retracted, a drill bitconnected to the lower end of the reamer housing, and means operable bymanipulation of the drill pipe from the surface of the well bore fordisconnecting the drilling assembly from the deflecting tool, wherebythe assembly may be subsequently lowered and rotated to perform adrilling operation which is guided by the deflecting tool.

9. A rotary earth bore drilling apparatus for drilling a bore at anangle to and of approximately the same diameter as a, bore extendingfrom the surface, said apparatus comprising a defleeting tool, arotatable drill pipe, means for connecting the deflecting tool to thedrill stem for lowering into the bore from the surface and for thenpermitting disconnection of the tool by a relative movement between thepipe and tool to thereby permit the pipe to rotate relatively to thetool, a drill bit rotatably connected to the lower end of the drill pipebelow its connection with the deflecting tool and capable of beingdeflected by the tool and by pipe rotation drilling a bore at an angleto and of less diameter than the bore from the surface, expansiblereaming means carried by the drill pipe above the drill bit and normallypositioned to be inoperative, and means operable by a relativelongitudinal movement of the drill pipe with respect to the reamingmeans for expanding the reaming means so that it will function toenlarge the bore drilled by the bit as the drill pipe is rotated.

10. A rotary earth bore drilling apparatus for drilling a bore at anangle to and of approximately the same diameter as a bore extending fromthe surface, said apparatus comprising a deflecting tool, a rotatabledrill pipe, means for connecting the deflecting tool to the drill stemfor .iowering into the bore from the surface and for then permittingdisconnection of the tool by a relative movement between the pipe andtool to thereby permit the pipe to rotate relatively to the tool, amember mounted on the lower end of the drill pipe below its connectionwith the deflecting tool for rotation with the pipe but capable of axialmovement with respect thereto, a drill bit mounted on said member andcapable of being deflected by the tool and by pipe rotation drilling abore at an angle to and of less diameter than the bore from the surface,expansible reaming means carried by the member above the drill bit andnormally positioned to be inoperative, and means 10- operable by themoving of the pipe relatively to the member for expanding the reamingmeans so as to enlarge the bore drilled by the bit as the pipe isrotated.

JAMES C. STATON.

REFERENCES CITED --The following references are of record in the file ofthis patent:

UNITED' STATES PATENTS Number Name Date 1,795,553 Getty Mar. 10, 19311,955,631 Harris Apr. 17, 1934 1,970,761 McVicar Aug. 21, 1934 2,108,419Trotter Feb. 15, 1938 2,120,670 Hyer June 14, 1938 2,327,658 Miller Aug.24, 1943

